在一家单独居住的小屋里生活，两个姐姐带着一个特殊的弟弟，为他保健身体。作家大江创作了一本关于父女情深与写作疑惑的小说，同时伊丹十三也在电影中尽可能地保留这些宝贵的内容。
这是一个平静而孤单的生活，父母出国后，智障的哥哥独自待在家中。为了他 brother's well-being, older sister Mei Aki takes her younger brother to learn swimming. However, the swim coach, Tachibana, has a complex past with their father. As events unfold, everything hangs in the balance for Mei Aki to solve this heart-wrenching mystery...
